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<pre>
<?php
	//set_errors(E_ALL);
	// Типы переменных
	#
	/*     */
	$var = 5;
	echo gettype($var)."\n";
	$var = 5.4;
	echo gettype($var)."\n";
	$var = "string";
	echo gettype($var)."\n";
	
	$a = 5;
	
	$str = 'a = $a';
	echo $str."\n";
	$str = "a = $a";
	echo $str."\n";
	echo '<input type="radio">'."\n";
	echo "<input type=\"radio\">\n";
	//echo `dir`;
	
	$b = TRUE; // FALSE
	echo gettype($b)."\n";
	
	$a = array(1,2,3);
	echo gettype($a)."\n";
	
	$fd = fopen('controls.php','r');
	echo gettype($fd)."\n";
	
	$fd = new DomDocument;
	echo gettype($fd)."\n";
	
	$a = NULL;
	echo gettype($a)."\n";
	
	unset($a); // delete $a
	
	//$b = $a;
	echo (isset($a))? '$a is set' : '$a isnt set';
	$a = "str";
	echo "\n";
	echo (isset($a))? '$a is set' : '$a isnt set';
	unset($a);
	echo "\n";
	echo (isset($a))? '$a is set' : '$a isnt set';
	
	// Константы
	define(PI, 3.14);

	echo PI."\n";
	
	echo __FILE__."\n";

	echo __LINE__."\n";
	echo PHP_VERSION."\n";
	echo PHP_OS."\n";
	
?>
</pre>
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